US raises legal age to buy cigarettes, vapes to 21

They'll still find an older person to buy them for them.

From a clinical perspective here are my observations: The peak age range in the US for substance abuse disorder (SUD) is 18 ~ 26. And the vast majority w/ SUD, consume multiple psychoactive substances (poly-sub abuse). So adjusting the age range, sadly, will do very little to deter folks from using. And nicotine is the #1 cause of premature morbidity and mortality, and alcohol is # 2.
Rich